/*=========================================================================

  Program:   Visualization Toolkit
  Module:    vtkPointInterpolator2D.h

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
// .NAME vtkPointInterpolator2D - interpolate point cloud attribute data
// onto x-y plane using various kernels

// .SECTION Description
// vtkPointInterpolator2D probes a point cloud Pc (the filter Source) with a
// set of points P (the filter Input), interpolating the data values from Pc
// onto P. Note however that the descriptive phrase "point cloud" is a
// misnomer: Pc can be represented by any vtkDataSet type, with the points of
// the dataset forming Pc. Similary, the output P can also be represented by
// any vtkDataSet type; and the topology/geometry structure of P is passed
// through to the output along with the newly interpolated arrays. However,
// this filter presumes that P lies on a plane z=0.0, thus z-coordinates
// are set accordingly during the interpolation process.
//
// The optional boolen flag InterpolateZ is provided for convenience. In
// effect it turns the source z coordinates into an additional array that is
// interpolated onto the output data. For example, if the source is a x-y-z
// LIDAR point cloud, then z can be interpolated onto the output dataset as a
// vertical elevation(z-coordinate).
//
// A key input to this filter is the specification of the interpolation
// kernel, and the parameters which control the associated interpolation
// process. Interpolation kernels include Voronoi, Gaussian, Shepard, and SPH
// (smoothed particle hydrodynamics), with additional kernels to be added in
// the future. See vtkPointInterpolator for more information.

// .SECTION Caveats
// This class has been threaded with vtkSMPTools. Using TBB or other
// non-sequential type (set in the CMake variable
// VTK_SMP_IMPLEMENTATION_TYPE) may improve performance significantly.
//
// For widely spaced points in Pc, or when p is located outside the bounding
// region of Pc, the interpolation may behave badly and the interpolation
// process will adapt as necessary to produce output. For example, if the N
// closest points within R are requested to interpolate p, if N=0 then the
// interpolation will switch to a different strategy (which can be controlled
// as in the NullPointsStrategy).

// .SECTION See Also
// vtkPointInterpolator

#ifndef vtkPointInterpolator2D_h
#define vtkPointInterpolator2D_h

#include "vtkFiltersPointsModule.h" // For export macro
#include "vtkPointInterpolator.h"
#include "vtkStdString.h"        // For vtkStdString ivars


class VTKFILTERSPOINTS_EXPORT vtkPointInterpolator2D : public vtkPointInterpolator
{
public:
  // Description:
  // Standard methods for instantiating, obtaining type information, and
  // printing.
  static vtkPointInterpolator2D *New();
  vtkTypeMacro(vtkPointInterpolator2D,vtkPointInterpolator);
  void PrintSelf(ostream& os, vtkIndent indent);

  // Description:
  // Specify whether to take the z-coordinate values of the source points as
  // attributes to be interpolated. This is in addition to any other point
  // attribute data associated with the source. By default this is enabled.
  vtkSetMacro(InterpolateZ,bool);
  vtkGetMacro(InterpolateZ,bool);
  vtkBooleanMacro(InterpolateZ,bool);

  // Description:
  // Specify the name of the output array containing z values. This method is
  // only applicable when InterpolateZ is enabled. By default the output
  // array name is "Elevation".
  vtkSetMacro(ZArrayName, vtkStdString);
  vtkGetMacro(ZArrayName, vtkStdString);

protected:
  vtkPointInterpolator2D();
  ~vtkPointInterpolator2D();

  // Interpolate z values?
  bool InterpolateZ;

  // Name of output array
  vtkStdString ZArrayName;

  // The driver of the algorithm
  virtual void Probe(vtkDataSet *input, vtkDataSet *source, vtkDataSet *output);

private:
  vtkPointInterpolator2D(const vtkPointInterpolator2D&);  // Not implemented.
  void operator=(const vtkPointInterpolator2D&);  // Not implemented.

};

#endif
